Stellar and Galactic Dynamics

The consequences of the virial theorem are important and differentiate the behavior of a gravitating cluster from a normal gas. Because the total energy is negative, a loss of mass causes the cluster to contract. This is familiar 

Single particle stellar orbital mechanics is not unlike planetary ring theory. Bodies move under the influence of a gravitational field created by the mutual interactions of all of the stellar masses in the system, a spatially extended and complicated potential. 

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